(B-299) Antibiotic-Related Side Effects and Infusion Reactions in Hospitalized Bacteremia and Sepsis Patients: Essential Data for Clinical Trials and Safety Monitoring

Background: New antibiotics are urgently needed to treat CRAB, a multidrug-resistant bacterial infection. Real-world data can provide crucial evidence to understand the adverse events experienced by patients diagnosed with serious bacterial infections to inform the planning of clinical trials and contextualize potential safety signals.

Objectives: To compare clinical characteristics and antibiotic-related side effects in hospitalized CRAB infection patients versus a general population of patients with bacteremia/sepsis.

Methods: This retrospective cohort study used records from a large, geographically representative U.S. claims database (IQVIA PharMetrics® Plus) from January 1, 2018 to October 31, 2024. We identified hospitalized patients of all ages diagnosed with (1) bacteremia and/or sepsis and (2) CRAB infections (ICD-10-CM). We summarized the patients’ demographic information, length of hospitalization, and comorbidities in the 12 months before hospitalization using the Charlson Comorbidity Index scores (CCIs). We then calculated the proportion of patients who developed antibiotic-related side effects and infusion-related reactions stratified by pediatric ( <18 yrs) and adult patients.

Results: We identified 1.5 million hospitalized patients with bacteremia/sepsis between 2018-2024 and 811 patients with an active CRAB infection between 2023-2024 (when CRAB-specific ICD codes first became available). Overall, adult patients with CRAB were similar in age to those with bacteremia/sepsis (mean 61 vs. 63 yrs). Pediatric patients made up a similar proportion of the overall cohort than for patients with CRAB (6% vs. 4%) and were slightly older (mean 5.1 vs. 3.6 yrs). Overall, CRAB patients experienced longer hospitalizations (22 vs. 10 days) and had more comorbidities (mean CCI 4.0 vs. 2.8).

Regarding antibiotic-related side effects, CRAB patients exhibited more dermatological and neurological complications, particularly seizures (12% vs. 4%). While gastrointestinal conditions were less common in adult CRAB patients (13% vs. 18%), they were more frequent in pediatric CRAB patients (19% vs. 14%). Overall, rates of nephrotoxicity, hepatic dysfunction, hypokalemia, hyperkalemia, and urinary tract infections were similar between the groups. However, CRAB patients had a higher incidence of infusion-related reactions (34% vs. 26%), septic shock (23% vs. 17%), and a greater need for renal replacement therapy (13% vs. 5%).

Conclusions: Patients infected with CRAB are critically ill with distinct demographics, more comorbidities, longer hospital stays, and higher rates of severe complications compared to a general cohort of patients with serious bacterial infections.